Move //mojo/{public, edk} underneath //third_party

mojo/public/cpp/utility/tests/mutex_unittest.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "mojo/public/cpp/utility/mutex.h"
-
-#include <stdlib.h>  // For |rand()|.
-#include <time.h>  // For |nanosleep()| (defined by POSIX).
-
-#include <vector>
-
-#include "mojo/public/cpp/system/macros.h"
-#include "mojo/public/cpp/utility/thread.h"
-#include "testing/gtest/include/gtest/gtest.h"
-
-namespace mojo {
-namespace {
-
-TEST(MutexTest, TrivialSingleThreaded) {
-  Mutex mutex;
-
-  mutex.Lock();
-  mutex.AssertHeld();
-  mutex.Unlock();
-
-  EXPECT_TRUE(mutex.TryLock());
-  mutex.AssertHeld();
-  mutex.Unlock();
-
-  {
-    MutexLock lock(&mutex);
-    mutex.AssertHeld();
-  }
-
-  EXPECT_TRUE(mutex.TryLock());
-  mutex.Unlock();
-}
-
-class Fiddler {
- public:
-  enum Type { kTypeLock, kTypeTry };
-  Fiddler(size_t times_to_lock,
-          Type type,
-          bool should_sleep,
-          Mutex* mutex,
-          int* shared_value)
-      : times_to_lock_(times_to_lock),
-        type_(type),
-        should_sleep_(should_sleep),
-        mutex_(mutex),
-        shared_value_(shared_value) {
-  }
-
-  ~Fiddler() {
-  }
-
-  void Fiddle() {
-    for (size_t i = 0; i < times_to_lock_;) {
-      switch (type_) {
-        case kTypeLock: {
-          mutex_->Lock();
-          int old_shared_value = *shared_value_;
-          if (should_sleep_)
-            SleepALittle();
-          *shared_value_ = old_shared_value + 1;
-          mutex_->Unlock();
-          i++;
-          break;
-        }
-        case kTypeTry:
-          if (mutex_->TryLock()) {
-            int old_shared_value = *shared_value_;
-            if (should_sleep_)
-              SleepALittle();
-            *shared_value_ = old_shared_value + 1;
-            mutex_->Unlock();
-            i++;
-          } else {
-            SleepALittle();  // Don't spin.
-          }
-          break;
-      }
-    }
-  }
-
- private:
-  static void SleepALittle() {
-    static const long kNanosPerMilli = 1000000;
-    struct timespec req = {
-      0,  // Seconds.
-      (rand() % 10) * kNanosPerMilli // Nanoseconds.
-    };
-    int rv = nanosleep(&req, nullptr);
-    MOJO_ALLOW_UNUSED_LOCAL(rv);
-    assert(rv == 0);
-  }
-
-  const size_t times_to_lock_;
-  const Type type_;
-  const bool should_sleep_;
-  Mutex* const mutex_;
-  int* const shared_value_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(Fiddler);
-};
-
-class FiddlerThread : public Thread {
- public:
-  // Takes ownership of |fiddler|.
-  FiddlerThread(Fiddler* fiddler)
-      : fiddler_(fiddler) {
-  }
-
-  ~FiddlerThread() override { delete fiddler_; }
-
-  void Run() override { fiddler_->Fiddle(); }
-
- private:
-  Fiddler* const fiddler_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(FiddlerThread);
-};
-
-// This does a stress test (that also checks exclusion).
-TEST(MutexTest, ThreadedStress) {
-  static const size_t kNumThreads = 20;
-  static const int kTimesToLockEach = 20;
-  assert(kNumThreads % 4 == 0);
-
-  Mutex mutex;
-  int shared_value = 0;
-
-  std::vector<FiddlerThread*> fiddler_threads;
-
-  for (size_t i = 0; i < kNumThreads; i += 4) {
-    fiddler_threads.push_back(new FiddlerThread(new Fiddler(
-        kTimesToLockEach, Fiddler::kTypeLock, false, &mutex, &shared_value)));
-    fiddler_threads.push_back(new FiddlerThread(new Fiddler(
-        kTimesToLockEach, Fiddler::kTypeTry, false, &mutex, &shared_value)));
-    fiddler_threads.push_back(new FiddlerThread(new Fiddler(
-        kTimesToLockEach, Fiddler::kTypeLock, true, &mutex, &shared_value)));
-    fiddler_threads.push_back(new FiddlerThread(new Fiddler(
-        kTimesToLockEach, Fiddler::kTypeTry, true, &mutex, &shared_value)));
-  }
-
-  for (size_t i = 0; i < kNumThreads; i++)
-    fiddler_threads[i]->Start();
-
-  // Do some fiddling ourselves.
-  Fiddler(kTimesToLockEach, Fiddler::kTypeLock, true, &mutex, &shared_value)
-      .Fiddle();
-
-  // Join.
-  for (size_t i = 0; i < kNumThreads; i++)
-    fiddler_threads[i]->Join();
-
-  EXPECT_EQ(static_cast<int>(kNumThreads + 1) * kTimesToLockEach, shared_value);
-
-  // Delete.
-  for (size_t i = 0; i < kNumThreads; i++)
-    delete fiddler_threads[i];
-  fiddler_threads.clear();
-}
-
-class TryThread : public Thread {
- public:
-  explicit TryThread(Mutex* mutex) : mutex_(mutex), try_lock_succeeded_() {}
-  ~TryThread() override {}
-
-  void Run() override {
-    try_lock_succeeded_ = mutex_->TryLock();
-    if (try_lock_succeeded_)
-      mutex_->Unlock();
-  }
-
-  bool try_lock_succeeded() const { return try_lock_succeeded_; }
-
- private:
-  Mutex* const mutex_;
-  bool try_lock_succeeded_;
-
-  MOJO_DISALLOW_COPY_AND_ASSIGN(TryThread);
-};
-
-TEST(MutexTest, TryLock) {
-  Mutex mutex;
-
-  // |TryLock()| should succeed -- we don't have the lock.
-  {
-    TryThread thread(&mutex);
-    thread.Start();
-    thread.Join();
-    EXPECT_TRUE(thread.try_lock_succeeded());
-  }
-
-  // Take the lock.
-  ASSERT_TRUE(mutex.TryLock());
-
-  // Now it should fail.
-  {
-    TryThread thread(&mutex);
-    thread.Start();
-    thread.Join();
-    EXPECT_FALSE(thread.try_lock_succeeded());
-  }
-
-  // Release the lock.
-  mutex.Unlock();
-
-  // It should succeed again.
-  {
-    TryThread thread(&mutex);
-    thread.Start();
-    thread.Join();
-    EXPECT_TRUE(thread.try_lock_succeeded());
-  }
-}
-
-
-// Tests of assertions for Debug builds.
-#if !defined(NDEBUG)
-// Test |AssertHeld()| (which is an actual user API).
-TEST(MutexTest, DebugAssertHeldFailure) {
-  Mutex mutex;
-  EXPECT_DEATH_IF_SUPPORTED(mutex.AssertHeld(), "");
-}
-
-// Test other consistency checks.
-TEST(MutexTest, DebugAssertionFailures) {
-  // Unlock without lock held.
-  EXPECT_DEATH_IF_SUPPORTED({
-    Mutex mutex;
-    mutex.Unlock();
-  }, "");
-
-  // Lock with lock held (on same thread).
-  EXPECT_DEATH_IF_SUPPORTED({
-    Mutex mutex;
-    mutex.Lock();
-    mutex.Lock();
-  }, "");
-
-  // Try lock with lock held.
-  EXPECT_DEATH_IF_SUPPORTED({
-    Mutex mutex;
-    mutex.Lock();
-    mutex.TryLock();
-  }, "");
-
-  // Destroy lock with lock held.
-  EXPECT_DEATH_IF_SUPPORTED({
-    Mutex mutex;
-    mutex.Lock();
-  }, "");
-}
-#endif  // !defined(NDEBUG)
-
-}  // namespace
-}  // namespace mojo